Anaemias and some other blood disorders

Before initiating treatment for anaemia it is essential to determine which type is present. Iron salts may be harmful and result in iron overload if given alone to patients with anaemias other than those due to iron deficiency.

Iron-deficiency anaemias

Treatment with an iron preparation is justified only in the presence of a demonstrable iron-deficiency state. Before starting treatment, it is important to exclude any serious underlying cause of the anaemia (e.g. gastric erosion, gastro-intestinal cancer). Prophylaxis with an iron preparation is justifiable in individuals who have additional risk factors for iron deficiency (e.g. poor diet). Prophylaxis may also be appropriate in malabsorption, menorrhagia, pregnancy, after subtotal or total gastrectomy, in haemodialysis patients, and in the management of low birth-weight infants such as preterm neonates.

FERROUS SULPHATE:

Indications: Iron Deficiency Anemia.

Contraindications: Hemochromatosis, Diverticular Disease, Esophageal Dysmotility, Gastroenteritis, Hemolytic Anemia, Hemosiderosis, Repeated Blood Transfusions, Ulcerative Colitis.

Dose and Administration: Prophylactic, 1 tablet (dried ferrous sulphate 190mg equivalent to 60mg elemental iron) daily; therapeutic, 1 tablet 2–3 times daily. Oral drops; infant and children, prophylactic, 0.6 mL (1ml contains 125mg ferrous sulphate equivalent to 25mg elemental iron) daily; therapeutic, up to 3ml daily in divided doses.

IRON (III) HYDROXIDE POLYMALTOSE COMPLEX:

Indications: Prevention and treatment of iron deficiency and iron-deficiency anemias.

Contraindications: Hypersensitivity to any ingredient, hemosiderosis, hemolytic anemia, hemochromatosis.

Dose and Administration: Adults and children over 12 years; tablets; in normal cases 1-2 tablets (100mg Iron) daily as per required. Syrup; 2- teaspoonful (50mg iron per 5ml) 1-2 times daily during or after meals. Children under 12 years; 1-teaspoonful 1-2 times daily. Infants; begin with 1/2 of a teaspoonful daily.

IRON (III) HYDROXIDE SACCHARATE COMPLEX:  Indications: Anemia of Prematurity, Iron Deficiency Anemia.

Contraindications: Chronic Iron Overload, Hemochromatosis, Hemosiderosis, and Hypotension.

Dose and Administration: 1^st day 2.5ml = 50mg iron. 2^nd day 5ml = 100mg iron. 3^rd day 10ml = 200mg iron to be followed with 10ml two times a week depending on hemoglobin level.

IRON (III) HYDROXIDE POLYMALTOSE COMPLEX-FOLIC

ACID:

Indications: Prevention and treatment of iron and folic acid deficiencies of all origins during pregnancy and lactation period.

Contraindications: Hypersensitivity to any ingredient, hemosiderosis, hemolytic anemia, hemochromatosis.

Dose and Administration: in normal cases 1 tablet (100mg iron & 350mcg folic acid) daily.

Drugs used in megaloblastic anaemias

Most megaloblastic anaemias result from a lack of either vitamin _B12 or folate, and it is essential to establish in every case which deficiency is present and the underlying cause. In emergencies, when delay might be dangerous, it is sometimes necessary to administer both substances after the bone marrow test while plasma assay results are awaited. Normally, however, appropriate treatment should be instituted only when the results of tests are available. One cause of megaloblastic anaemia in the is pernicious anaemia in which lack of gastric intrinsic factor resulting from an autoimmune gastritis causes malabsorption of vitamin B12.

CYANOCOBALAMIN:

Indications: Cyanocobalamin is indicated for vitamin B12 deficiencies due to malabsorption which may be associated with the following conditions: Addisonian (pernicious) anemia, Gastrointestinal pathology, dysfunction, or surgery, including gluten enteropathy or sprue, small bowel bacteria overgrowth, total or partial gastrectomy, Fish tapeworm infestation, Malignancy of pancreas or bowel and Folic acid deficiency.

Contraindications: Leber’s Hereditary Optic Atrophy.

Dose and Administration: Pernicious Anemia: A dose of 100 mcg daily for 6 or 7 days should be administered by intramuscular or deep subcutaneous injection. If there is clinical improvement and if a reticulocyte response is observed, the same amount may be given on alternate days for seven doses, then every 3 to 4 days for another 2 to 3 weeks. By this time hematologic values should have become normal. This regimen should be followed by 100 mcg monthly for life. Folic acid should be administered concomitantly if needed.

FOLIC ACID:

Indications: Folic Acid is effective in the treatment of megaloblastic anemias due to a deficiency of Folic Acid (as may be seen in tropical or nontropical sprue) and in anemias of nutritional origin, pregnancy, infancy, or childhood.

Contraindications: Folic Acid is contraindicated in patients who have shown previous intolerance to the drug.

Dose and Administration: Folate-deficient megaloblastic anaemia, by mouth, adult and child over 1 year, 5 mg daily for 4 months (until term in pregnant women); up to 15 mg daily may be required in malabsorption states; maintenance, 5 mg every 1–7 days; child under 1 year, 500 micrograms/kg daily for up to 4 months; maintenance 500 micrograms/kg every 1–7 days. Prophylaxis of folate deficiency in dialysis, by mouth, adult 5 mg every 1–7 days; child 1–12 years 250 micrograms/kg (max. 10 mg) once daily, child 12–18 years 5–10 mg once daily.

Drugs used in hypoplastic, haemolytic, and renal anaemias

Erythropoietins

used to treat the symptomatic anaemia associated with erythropoietin deficiency in chronic renal failure, to increase the yield of autologous blood in normal individuals and to shorten the period of symptomatic anaemia in patients receiving cytotoxic chemotherapy.

EPOETIN ALFA:

Indications: Treatment of anemia related to chronic renal failure (CRF), anemia related to zidovudine therapy in HIV-infected patients, and anemia due to chemotherapy in patients with metastatic nonmyeloid malignancies; reduction of allogeneic blood transfusions in surgery patients.

Contraindications: Severe Uncontrolled Hypertension, Acute Decompensated Heart Failure, Cerebrovascular Accident, Constitutional Aplastic Anemia, Coronary Artery Disease, Deep Venous Thrombosis, Myocardial Infarction, Pulmonary Thromboembolism, Thromboembolic Disorder, Thrombophlebitis.

Dose and Administration: IV / Subcutaneous Individually titrate to achieve and maintain Hgb levels between 10 and 12 g/dL. Increases in dose should not be made more often than once monthly. Start with 50 to 100 units/kg 3 times/wk. Increase the dose by 25% if the Hgb is less than 10 g/dL and has not increased by 1 g/dL after 4 wk of therapy or if the Hgb decreases below 10 g/dL. Reduce the dose by 25% when the Hgb approaches 12 g/dL or the Hgb

increases by more then 1 g/dL in any 2-wk period. If the Hgb continues to increase, temporarily withhold the dose until the Hgb begins to decrease, then reinitiate treatment at a dose approximately 25% below the previous dose.

DARBEPOETIN ALFA:

Indications: Treatment of anemia associated with chronic renal failure (CRF), whether or not the patient is on dialysis; treatment of anemia in patients with nonmyeloid malignancies in whom anemia is caused by coadministered chemotherapy.

Contraindications: Severe Uncontrolled Hypertension, Acute Decompensated Heart Failure, Cerebrovascular Accident, Constitutional Aplastic Anemia, Coronary Artery Disease, Deep Venous Thrombosis, Myocardial Infarction, Pulmonary Thromboembolism, Thromboembolic Disorder, Thrombophlebitis and breast-feeding.

Dose and Administration: IV/Subcutaneous 0.45 mcg/kg as a single dose once weekly. Alternatively, in patients not receiving dialysis, start with 0.75 mcg/kg as a single subcutaneous injection once every 2 weeks. Individualize the dose to maintain Hgb levels within the range of 10 to 12 g/dL.

Iron overload

Severe tissue iron overload can occur in aplastic and other refractory anaemias, mainly as the result of repeated blood transfusions. It is a particular problem in refractory anaemias with hyperplastic bone marrow, especially thalassaemia major, where excessive iron absorption from the gut and inappropriate iron therapy can add to the tissue siderosis.

DESFERRIOXAMINE MESILATE:

Indications: Deferoxamine mesylate for injection is indicated for the treatment of acute iron intoxication and of chronic iron overload due to transfusion-dependent anemias.

Contraindications: Oliguria, Renal Disease and Mucormycosis.

Dose and Administration: A dose of 1000 mg should be administered initially. This may be followed by 500 mg every 4 hours for two doses. Depending upon the clinical response, subsequent doses of 500 mg may be administered every 4- 12 hours. The total amount administered should not exceed 6000 mg in 24 hours.

Drugs used in neutropenia

Recombinant human granulocyte-colony stimulating factor (rhG-CSF) stimulates the production of neutrophils and may reduce the duration of chemotherapy-induced neutropenia and thereby reduce the incidence of associated sepsis; there is as yet no evidence that it improves overall survival.

FILGRASTIM:

Indications: reduction in duration of neutropenia and incidence of febrile neutropenia in cytotoxic chemotherapy for malignancy (except chronic myeloid leukaemia and myelodysplastic syndromes); reduction in duration of neutropenia (and associated sequelae) in myeloablative therapy followed by bone-marrow transplantation; mobilisation of peripheral blood progenitor cells for harvesting and subsequent autologous or allogeneic infusion; severe congenital neutropenia, cyclic neutropenia, or idiopathic neutropenia and history of severe or recurrent infections.

Contraindications: severe congenital neutropenia (Kostmann’s syndrome) with abnormal cytogenetics.

Dose and Administration: Cytotoxic-induced neutropenia, preferably by subcutaneous injection or by intravenous infusion (over 30 minutes), adult and child, 500 000 units/kg daily started at least 24 hours after cytotoxic chemotherapy, continued until neutrophil count in normal range, usually for up to 14 days (up to 38 days in acute myeloid leukaemia). Myeloablative therapy followed by bone-marrow transplantation, by intravenous infusion over 30 minutes or over 24 hours or by subcutaneous infusion over 24 hours, 1 million units/kg daily, started at least 24 hours following cytotoxic chemotherapy (and within 24 hours of bone-marrow infusion), then adjusted according to neutrophil count. Severe chronic neutropenia, by subcutaneous injection, adult and child, in severe congenital neutropenia, initially 1.2 million units/kg daily in single or divided doses (initially 500 000 units/kg daily in idiopathic or cyclic neutropenia), adjusted according to response.

PEGFILGRASTIM:

Indications: reduction in duration of neutropenia and incidence of febrile neutropenia in cytotoxic chemotherapy for malignancy (except chronic myeloid leukaemia and myelodysplastic syndromes).

Contraindications: Hypersensitivity to filgrastim, pegfilgrastim, or any component of the product.

Dose and Administration: Subcutaneous 6 mg once per chemotherapy cycle.